Freshwater fish helminths, the most well known Mexican vertebrate parasites, include approximately 260 species (platyhelminthes, acanthocephalans, nematodes, and hirudineans). The distribution patterns of adult helminth diversity (throughout parasite and host groups and hydrological regions) are described and the effects of host traits and environmental and geographical factors on diversity are evaluated. Adult helminths include 160 species, parasitizing 149 fish species of 23 families distributed in 21 regions. Nematoda was the most species-rich (>50 species). Cichlidae harboured rich helminth assemblages, with widespread parasites. By contrast, Atherinopsidae and Goodeidae showed relatively poor helminth assemblages, including specific parasites with narrow distribution. Helminth richness in southeastern Mexico was higher than northern or central regions. Non-parametric richness estimators were used to avoid confusion in comparisons with unequal sampling efforts. Bootstrap values, the method with the best performance, indicated that estimated richness shows the same distribution pattern that observed richness. Non-phylogenetic and phylogenetic analyses were used to determine the role of different factors in the parasite diversification. The distribution range was the most important richness predictor (widespread fishes harbour richer parasite assemblages), although interactions between this variable and others such as trophic level, latitude, habitat temperature and precipitation are also important. Likewise, biogeographical factors can also affect parasite diversity.

The evolutionary relationships of the eutherian order Insectivora (Lipotyphla sensu stricto) are the subject of considerable debate. The difficulties in establishing insectivore phylogeny stem from their lack of many shared derived characteristics. The grouping is therefore something of a ‘wastebasket’ taxon. Most of the older estimates of phylogeny, based on morphological evidence, assumed insectivore monophyly. More recently, molecular phylogenies argue strongly against monophyly, although they differ in the extent of polyphyly inferred for the order. I review the history of insectivore phylogenetics and systematics, focussing on the relationships between the six extant families (Erinaceidae – hedgehogs and moonrats, Talpidae – moles and desmans, Soricidae – shrews, Solenodontidae – solenodons, Tenrecidae – tenrecs and otter-shrews and Chrysochloridae – golden moles). I then examine how these various phylogenetic hypotheses influence the results of comparative analyses and our interpretation of insectivore life-history evolution. I assess which particular controversies have the greatest effect on results, and discuss the implications for comparative analyses where the phylogeny is controversial. I also explore and suggest explanations for certain insectivore life-history trends: increased gestation length and litter size in tenrecs, increased encephalization in moles, and the mixed fast and slow life-history strategies in solenodons. Finally, I consider the implications for comparative analyses of the recent strongly supported phylogenetic hypothesis of an endemic African clade of mammals that includes the insectivore families of tenrecs and golden moles.

This study is the first attempt to use both independent contrasts and cross-genera correlation for the family Accipitridae to see if population density and body weight are associated with other ecological or morphological variables. Using literature data on nine variables for 189 species of 35 genera, significant associations between contrasts in population density and reproductive rate and hunting method were found. Cross-genera correlation results differed because all morphological variables were negatively correlated with population density while none of these correlations was significant using independent contrasts. Contrasts in body weight were positively correlated with mean prey weight and negatively with range size. Overall, reproductive rate had the highest correlations with population density.

The morphospace defined by 87 species of ground beetle (Coleoptera: Carabidae) of Scottish non-forested habitats is described with multivariate methods, using 13 linear quantitative measurements of the body, hind legs, eyes and antennae, plus five qualitative characters concerned with body shape, colour, wing development, and pubescence. Relationships between pairs of variables are studied with phylogenetic independent contrasts, using two different taxonomic classifications as an approximation to the phylogeny of the group. The first ordination axis of the morphospace was found mainly to reflect the positive correlation between length of the antennae and length of the hind legs, the second to reflect the width of the head, diameter of the eye and pronotum height, and the third the width of the pronotum and elytra, length of the metatrochanter and width of the metafemur. The principal relationships involving qualitative characters were between colour of the body and legs and shape of the pronotum with ordination axes, wing development with width of the elytra, and pubescence with colour of the legs. Most correlations between quantitative variables, in particular those most influencing the ordination axes of the morphospace, remained significant when measured with phylogenetic independent contrasts using both classifications. Independent contrasts comparing qualitative with quantitative variables or ordination axes were only significant for the colour of the body with the second axis for both classifications used, and length of the antennae with colour of the body and shape of the pronotum for only one of the classifications. The main morphological trends within the morphospace defined are related with published information on their performance, in particular running speed and pushing abilities, following previous work on the functional morphology of the group. The morphospace defined by the species studied is a fundamental tool that will allow further investigations on the relationships between their morphology and life traits, as well as on the relationships of the functional diversity thus characterized with environmental correlates.